- The following is an archived discussion of a featured article nomination. Please do not modify it. Subsequent comments should be made on the article's talk page or in Wikipedia talk:Featured article candidates. No further edits should be made to this page.
The article was promoted 04:25, 4 November 2007.
For your consideration, I'm nominating this article for FA status. It has undergone expansion and review during the past month, and I believe it is now well-referenced and reasonably comprehensive. The number of illustrations may be considered low, but this is partly a result of an article on a transparent gas: I didn't want to overburden the article with images that may be only indirectly related (such as a nuclear reactor rod, for example). Please let me know your concerns and I'll try to address them. Thank you. — RJH (talk) 18:50, 21 October 2007 (UTC)[reply]
- Support Great improvement on my original de-stub from several years ago. I just wish I beat you to bringing this to FA quality. ;) --mav 23:14, 21 October 2007 (UTC)[reply]
- Support. This is probably the most comprehensive article on xenon I have seen anywhere. Most chemical encyclopedias and textbooks lump it with the other noble gases, where helium and argon steal much of the attention. The nominated article is certainly much more comprehensive than the one at britannica.com. --Itub 08:09, 22 October 2007 (UTC)[reply]
Object for now, here's why:
- Are there any reactions described for other noble gasses or is Xe unique in that regard? (How much fun. The inaccuracies they teach you in school.)
the result may indicate that Mars lost most of its primordial atmosphere, possibly within the first 100 million years." First 100 million years of what? Its existence?
DoneAddressed. — RJH (talk) 14:58, 22 October 2007 (UTC)[reply]
- "As a liquid, xenon has a density of 3.52 g/mL, about 3.5 times the density of water." At what pressure is that?
DoneThe "Handbook of Inorganic Chemicals" doen't give a pressure for the liquid phase of xenon. — RJH (talk) 15:06, 22 October 2007 (UTC)[reply]
- Done, I've added a reference for the liquid density. --Itub 09:37, 23 October 2007 (UTC)[reply]
- "Using gigapascals of pressure, xenon has been forced into a metallic phase." What does this metallic phase look like?
Not doneIf a diamond anvil cell is used to produce the pressure, how would we be able to see it? I have no idea. — RJH (talk) 14:58, 22 October 2007 (UTC)[reply]
- There's nothing that can be said about how it "looks". I don't see why this can be an objection to featuring the article, if the original sources don't say anything about how it looks (probably because no one knows!). May I point out that the articles on hydrogen and metallic hydrogen don't say how metallic hydrogen looks either, for the same reason? And that hydrogen is featured? --Itub 09:23, 23 October 2007 (UTC)[reply]
- It's probably a good idea to briefly explain what clathrates.
Done I believe it does: "As well as compounds where xenon forms a chemical bond, xenon can form clathrates—substances where xenon atoms are trapped by the crystalline lattice of another compound." Does this need further clarification? — RJH (talk) 14:58, 22 October 2007 (UTC)[reply]
- I swear that explanation wasn't there when I read it... - Mgm|(talk) 17:37, 22 October 2007 (UTC)[reply]
- That might be. I think I had an explanation in there at one point but a few editors have been changing some of the details because of the Scientific PR. It's one of the 'joys' of working on a collaborative wiki. =) — RJH (talk) 14:40, 23 October 2007 (UTC)[reply]
- "Because of the high cost of xenon, however, economic application will require a closed system so that the gas can be recycled.[17]" Is that smart? What about the danger of airborne viral infections?
Done I added a note. — RJH (talk) 14:59, 23 October 2007 (UTC)[reply]
- Since Xe is so expensive, what are the advantages of using Xenon when other cheaper methods are available?
Done In what particular context? Many of the applications already explain this. — RJH (talk) 14:59, 23 October 2007 (UTC)[reply]
- Forget it. Apparently another explanation appeared out of nowhere. - Mgm|(talk) 21:20, 23 October 2007 (UTC)[reply]
- And finally, perhaps it's just my personal preference, but I would like people who read just the introduction to be able to find the sources without scouring the entire article. - Mgm|(talk) 09:45, 22 October 2007 (UTC)[reply]
DoneI re-used some refs. for the lead. — RJH (talk) 14:59, 23 October 2007 (UTC)[reply]
- Some replies (I've turned your bullet points into numbered items for ease of reference; I hope you don't mind):
- 1. There are reactions for some of the other noble gases, which are described in the relevant articles. But perhaps a brief comparison could be made here.
- 2. The infobox references are linked at the bottom of the table; see Chemical elements data references. This is the standard practice for element infoboxes, and is the same as in other featured articles such as hydrogen, uranium, titanium, helium, and francium.
- That links to a bunch of general references, not any specific to Xe. I want to know exactly what page was used. - Mgm|(talk) 10:45, 22 October 2007 (UTC)[reply]
- That's not true, you can find the exact reference for xenon in each of the data tables. For example, if you go to Boiling_points_of_the_elements_(data_page), you'll find three references and values for Xenon (and all of the other elements), as well as the recommended value that was chosen by WikiProject Elements. --Itub 10:58, 22 October 2007 (UTC)[reply]
- 3. First 100 million years since the formation of the planet (if not, since when? I can't think of any other meaning.).
- 4. Density doesn't change that much with pressure, so the pressure is often omitted in casual conversation. Standard conditions are 1 atmosphere or 1 bar. However, this should be checked.
- 5. What do you mean by "look like". I really doubt that anyone has literally "looked" at this substance, given that it must be inside a contraption that stands enormous pressures.
- Then how do they know they've got it? Perhaps things like color of the solid phase can be predicted? - Mgm|(talk) 10:45, 22 October 2007 (UTC)[reply]
- I suspect they detected the phase change thermodynamically, and they probably identified the metallic phase by its electrical conductivity. I don't think such details belong in an article about Xenon. Interested readers can look up the references, although eventually we could create an article about metallic xenon (as we have one already on metallic hydrogen) where all those details could be elaborated. --Itub 10:58, 22 October 2007 (UTC)[reply]
- 6. I'm not sure what you are asking about the clathrates. Could you clarify the question?
- I think a brief definition should be given for people who don't have Lupin's popups enabled. It's one of those sci-speak words. - Mgm|(talk) 10:45, 22 October 2007 (UTC)[reply]
- There is already a brief definition in the article: "[compounds] where xenon atoms occupy vacancies in a lattice of water molecules". But perhaps the definition could be clarified further. --Itub 10:58, 22 October 2007 (UTC)[reply]
- 7. I'm sure they've worked out ways of filtering the xenon properly, but that might be worth looking into.
- 8. Good question.
- 9. No comments.--Itub 10:20, 22 October 2007 (UTC)[reply]
- Another question: Since Xenon is described as colorless, do we really need an image in the appearance field of the infobox? - Mgm|(talk) 10:45, 22 October 2007 (UTC)[reply]
- Some people like those images, which is why they are found in all element infoboxes, even for invisible substances... I personally don't care much for this image. --Itub 10:58, 22 October 2007 (UTC)[reply]
- I'm having trouble in seeing the added value. The image at Invisible pink unicorn has a comedical element, any other atom article has an image with an informative element. I see neither in this image. - Mgm|(talk) 17:38, 22 October 2007 (UTC)[reply]
- It's not true that "any other atom article has an image with an informative element". The featured article on hydrogen and helium have pictures that look exactly like the one for xenon (because the elements look the same). I would rather keep the photo for consistency, and because it helps illustrate the "invisibility" of the element in a visual way, for readers that haven't read the part of the text that describes it as a "colorless gas". But as I said, I don't care that much for the image. I see it just as a minor matter of preference, and don't see how it can be an objection to featuring the article. --Itub 09:08, 23 October 2007 (UTC)[reply]
- An identical image is used on the hydrogen article. I suppose it's there for consistency, and it conveys the information that it's a transparent gas visually. Personally I would have preferred a transparent container that showed the seal, but this seems minimally sufficient for its purpose. — RJH (talk) 14:36, 23 October 2007 (UTC)[reply]
- Support Excellent, well-written article. I confess, I was not aware xenon could even form compounds. Would it be possible, for the liberal arts majors like me, to explain a little more how this is possible? If not, I;d still support, but it might make it more understandable to laymen. Coemgenus 15:15, 23 October 2007 (UTC)[reply]
- I added a couple of sentences near the end of the History section that I hope will explain how the first compound was produced; at least according to my admittedly very modest understanding of chemistry. — RJH (talk) 00:25, 24 October 2007 (UTC)[reply]
- Yes, that's much better. Coemgenus 16:07, 24 October 2007 (UTC)[reply]
- Support Well-written article. FA quality.--Tamás Kádár 15:54, 23 October 2007 (UTC)[reply]
- Support. My objections have mostly been addressed. A few explanations like how metallic xenon can be detected and for the question Coemgenus (talk · contribs) posed would help strengthen my support, but this is pretty much close to perfection. (If the photo of the colorless gas is kept I'd also like to see a more detailed description on the image page telling us exactly in what state the gas was photographed and more importantly, what was on the background. - Mgm|(talk) 21:25, 23 October 2007 (UTC)[reply]
- Unfortunately I wasn't able to find a suitable replacement image of some transparent laboratory glassware used to hold a gas. Perhaps this is something that one of the Chemistry WikiProjects would like to address? Or I could just whip up a rendered image of such with my Bryce software package. — RJH (talk) 00:35, 24 October 2007 (UTC)[reply]
- Support Comprehensive, well-written, maybe a little technical in the end sections, but, hey, that's fine. I'd consider explaining the terms "Spin 1/2" and "Colour temprature" a little more explicitly, the others seem fine. Adam Cuerden talk 06:54, 24 October 2007 (UTC)[reply]
- I included explanations for the terms "Spin ½" and "color temperature". Thank you for pointing them out. — RJH (talk) 16:30, 27 October 2007 (UTC)[reply]
- Support
Comments. I have a few comments:
- 1) Infobox lists fusion and boiling temperatures, but does not specify relevant pressures. While they are probably 1 atm, it is necessary to write them, because fusion and boiling (especially) points depend on pressure.
- Yes that would be good. The problem for me is when the references don't list the pressures. I didn't see one listed in the CRC I googled. This may be an issue that the Chemistry WikiProject needs to tackle for all of the elements. — RJH (talk) 17:52, 25 October 2007 (UTC)[reply]
- See Notes in the Boiling_points_of_the_elements_(data_page). Ruslik 05:49, 26 October 2007 (UTC)[reply]
:2) The density is expressed either in g/cm3 (or kg/m3) or in g/mL or kg/L. I think the article should use a uniform set of units. I suggest using g/cm3 and kg/m3. The same can be said about the units of volume: L and mL should be substituted with cm3 and m3.
- I left a question about this on Wikipedia talk:WikiProject Elements. — RJH (talk) 19:20, 25 October 2007 (UTC)[reply]
:3) The article says that Xenon is produced in SN explosions (r-process). It is only partly true. Some Xenon isotops are exclusevly made by p-process (124, 126) and s-procees (128, 130)—see [1], [2], [3]. The first process takes place in AGB stars and the second only partialy in SNII with a contribution from classical novae.[4]
- Thank you. I wasn't sure how much detail was needed for the purposes of this article, so for now I just inserted a summary sentence. But it could easily be expanded by somebody with access to all of those references. (I usually can't access very recent ApJ articles.) — RJH (talk) 17:41, 25 October 2007 (UTC)[reply]
:4) There are a few duplications in the article: the fourth paragraph in 'History' section largely overlaps with the last paragraph in 'Isotopes'; and the last paragraph in 'History' duplicates the first paragraph in 'Compounds'.
- They are only slightly overlapping; by no means complete duplications. I think the mild overlap is needed for flow. — RJH (talk) 15:45, 25 October 2007 (UTC)[reply]
- Ok, but I continue to think that duplication can be slightly reduced. Ruslik 05:49, 26 October 2007 (UTC)[reply]
:5) The first sentence in the last paragraph of 'Illumination and optics' subsection should be moved to the second paragraph.
- Huh? That action doesn't make sense from a context perspective. Perhaps this was fixed already? — RJH (talk) 15:48, 25 October 2007 (UTC)[reply]
- I meant "The first solid-state laser, invented in 1960, was pumped by a xenon flashlamp.", which have been already removed.Ruslik 05:49, 26 October 2007 (UTC)[reply]
:6) In 'Occurrence' section of the article prices of Xe are specified in euros as of 1999, while 'Anesthesia' subsection lists them in USD as of 2005. Can more uniform set of prices be used?
- I removed the later from the article so that there is only one price listed. — RJH (talk) 15:39, 25 October 2007 (UTC)[reply]
:7) In 'Other' subsection psi are used as units for pressure. They should be converted into Pa or bar.
- Fixed. — RJH (talk) 19:20, 25 October 2007 (UTC)[reply]
I hope my suggestions will be helpful. Ruslik 08:52, 24 October 2007 (UTC)[reply]
- Note, there's nothing wrong with redlinks and their removal is not required for FA status, unless the link is to a topic that is unlikely to attain notability. SandyGeorgia (Talk) 18:50, 30 October 2007 (UTC)[reply]
- Comments. The first footnote in compounds section points to 38 which seems a odd publication for the first synthesis of a xenon compound. The Xenon hexafluoroplatinate article provides the original anouncement in 1962.--Stone 16:45, 24 October 2007 (UTC)[reply]
- The first mentioning in the history section is also noted with a strange article mostly concerning other things than Xenon hexafluoroplatinate.--Stone 16:52, 24 October 2007 (UTC)[reply]
- Support Another elements is ready for FA!--Stone 08:38, 26 October 2007 (UTC)[reply]
Pass & support
- On the basis that it's well-done.
Remark: I especially admire the extensive Applications section. Leranedo 09:30, 29 October 2007 (UTC)[reply]
- The above discussion is preserved as an archive. Please do not modify it. Subsequent comments should be made on the article's talk page or in Wikipedia talk:Featured article candidates. No further edits should be made to this page.